JP2008038266A - Multilayer paper and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer paper obtained by manufacturing a nonwoven fabric by using a single fiber or a sheath-core conjugate fiber having a component of a polyvinyl alcohol (PVA), and then making pulp fibers with the nonwoven fabric by using a Fourdrinier paper machine, and a method for producing the same. <P>SOLUTION: This multilayer paper is obtained by preparing the nonwoven fabric by using the single-structured fiber having the PVA component having a thermally fusing temperature of 90-120°C, or the sheath-core conjugate fiber consisting of a resin having a thermally fusing temperature of >120°C at the core part, and the PVA fiber having a thermally fusing temperature of 90-120°C at the sheath part, interposing the nonwoven fabric between an upper layer paper material and lower layer paper material to form the multilayer paper having the upper paper material layer, nonwoven fabric layer and lower paper material layer and heating for drying the multilayer paper in a drying process of the papermaking machine. The method for producing the same is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention uses a single fiber or core-sheath type composite fiber made of polyvinyl alcohol (hereinafter referred to as “PVA”) as a raw material to produce a non-woven fabric by a wet method, and combines with a pulp fiber with a long net paper machine. The present invention relates to a multilayer laminated paper and a method for producing the same.

  As a general method for producing multilayer laminated paper, a raw material tank containing raw materials containing water and fibers is prepared according to the number of layers to be combined, and a mesh-like circular net is provided in the raw material tank. The fibers in the raw material tank are scooped up by a net to form a fiber web, the web is transferred to a net-like transport belt such as a wire, and the fiber webs formed by other raw material tanks and a circular net are sequentially stacked to make a multilayer plow. Methods for producing laminated paper are known.

  In the above-described method, there is a problem that a raw material tank and a net are required for the number of layers to be combined. This problem is solved by using a single long net, installing a slice for discharging and rectifying a plurality of raw materials on the long net, and sequentially stacking the raw materials on the long net. However, in this method, since the raw material is squeezed until it loses fluidity on the long net and is laminated after forming the web, the hydrogen bond between the fibers between the layers becomes weak, and the paper after papermaking peels off. There was a problem that it was easy.

  As a means to prevent such delamination of paper, when manufacturing multi-layered paper with multiple circular paper machines, or when manufacturing multi-layered paper by combining circular paper machines and long paper machines In addition, when a multi-layered paper is manufactured by combining a long paper machine and a long paper machine, a method of applying an adhesive with a spray device or a roll coater at the stage of the bonding has been proposed.

  In addition, when producing multi-layered laminated paper with a single long paper machine, a plurality of tanks containing raw materials including water and fibers are placed on a circulating endless paper net, and the width of the endless paper net In a long net paper machine in which at least one sheet and a feeding unit for feeding a sheet of an arbitrary width are installed below, in a tank arranged at a position preceding the endless paper making circuit circulation process among a plurality of tanks The raw material is discharged onto an endless paper mesh, and at least one layer of the raw material laminar flow is formed on the endless paper mesh, and then the sheet is run over the laminar flow, and further, a plurality of tanks are placed on the sheet. A multilayer laminated paper has been proposed in which a raw material in a tank disposed at a later position with respect to the endless papermaking mesh circulation process is discharged to form a wet web on the endless papermaking net. This sheet of laminated paper is a non-woven fabric using natural fibers such as rayon. By joining these non-woven fabrics of natural fibers, hydrogen bonding (interfiber bonding) occurs, and interlayer adhesion is obtained by interlaminar bonding. This is a means for preventing peeling (see, for example, Patent Document 1).

  In addition, a spunbond nonwoven fabric that has a core-sheath structure and the sheath part contains fibers of a heat-fusible resin whose melting point is lower than that of the core part, and the nonwoven fabric surface is laminated continuously or discontinuously by wet papermaking The papermaking layer is laminated to the nonwoven fabric in the form of a wet sheet formed by the wet part of the papermaking machine, and the papermaking layer and the nonwoven fabric are connected via a low melting point heat-meltable resin in the sheath portion of the nonwoven fabric. A multilayer laminated paper that is bonded by thermal melting has been proposed (see, for example, Patent Document 2).

  In addition, a paper is proposed that is configured by adding a design or functional material by printing or the like to PVA, which is a water-soluble and light-transmitting synthetic resin, and inserting it between two paper layers (for example, (See Patent Document 3).

  In addition, a multilayer paper has also been proposed in which a nonwoven fabric produced using polyethylene fiber, polyester fiber, polypropylene fiber or the like is sandwiched between wet paper and wet paper, and is produced by thermal fusion.

JP 2003-13395 A Japanese Patent No. 2784292 JP-A-63-270898

  However, in the method of applying the adhesive with the spray device or the roll coater as described above, the adhesive strength between the wet paper and the nonwoven fabric surface is improved because the adhesive is combined before drying, but the strength in the nonwoven fabric layer is increased. When it is low, delamination occurs in the nonwoven fabric layer.

  In addition, the method using a non-woven fabric using natural fibers such as rayon as disclosed in Japanese Patent Application Laid-Open No. 2003-13395 does not provide a sufficient adhesive force between the fibers of the rayon fibers and the wet paper fibers, and delamination does not occur. Will occur.

  In addition, a multilayer laminated paper produced using a spunbond nonwoven fabric made of a synthetic resin fiber, such as Japanese Patent No. 2784292, is a laminated multilayer paper because the spunbond nonwoven fabric itself lacks uniformity. Laminated paper also lacks uniformity, deteriorating appearance, printability and paper characteristics.

  In addition, a paper made by inserting a film made of PVA as disclosed in Japanese Patent Application Laid-Open No. 63-270898 between the paper layers, although the problem of delamination is almost avoided, the inserted film material is to some extent. The problem is that it is limited, and PVA comes into contact with the wet paper layer to absorb moisture, causing abrupt contraction and deformation of the applied pattern, etc. was there.

Moreover, since the method using the nonwoven fabric produced using polyethylene fiber, polyester fiber, polypropylene fiber, etc. has water repellency, the nonwoven fabric and upper and lower pulp fibers (wet paper) The affinity is poor, and delamination occurs.

  The present invention aims to solve the above-described problems. Specifically, the fiber length is 2 to 9 mm made of PVA, the fiber thickness is 0.6 to 5.6 dtex, and the thermal fusion temperature of PVA is 90 to 90. To provide a multilayer laminated paper in which a non-woven fabric is produced by wet using a fiber having a single structure or a core-sheath type composite fiber having a cross section of 120 ° C., and laminated with pulp fibers by a long net paper machine, and a method for producing the same. Objective.

  The method for producing a multilayer laminated paper of the present invention comprises preparing a non-woven fabric in advance by a wet process using fibers having at least a polyvinyl alcohol component, and forming a non-woven fabric made of polyvinyl alcohol between an upper layer paper material and a lower layer paper material on a paper machine. A multilayer laminated paper having an upper layer paper layer, a non-woven fabric layer and a lower layer paper layer is formed, and the multilayer laminated paper is heated and dried in the drying process of the paper machine.

  The method for producing a multilayer laminated paper of the present invention is such that the paper machine is a long paper machine, at least supplying an upper layer stock by means of an upper layer stock supply tank on a wire, and supplying a non-woven fabric by a non-woven fabric supply device, Water is removed from the multi-layered laminated paper, which is supplied by supplying the lower layer stock from the lower layer stock supply tank, with a water squeezing box and a press roll, and dried with a heat drying apparatus.

  The method for producing a multilayer laminated paper of the present invention is characterized in that the fiber having a polyvinyl alcohol component is a single fiber or a core-sheath type composite fiber.

  In the method for producing a multilayer laminated paper of the present invention, the core portion of the core-sheath type composite fiber is made of a resin having a heat-sealing temperature exceeding 120 ° C., and the sheath portion has polyvinyl alcohol having a heat-sealing temperature lower than that of the core portion. It is characterized by comprising.

  The method for producing a multilayer laminated paper of the present invention is characterized in that the heat-sealing temperature of the fiber having the polyvinyl alcohol component is within the range of the heat-drying temperature in the drying process in the paper machine. In the present invention, the fiber having a polyvinyl alcohol component has a heat fusion temperature of 90 to 120 ° C., and the heating and drying temperature in the drying process in the paper machine is 70 to 120 ° C.

  The method for producing a multilayer laminated paper of the present invention is characterized in that the fiber length of the fiber having a polyvinyl alcohol component is 2 to 9 mm and the thickness is 0.6 to 5.6 dtex.

The method for producing a multilayer laminated paper of the present invention is characterized in that the basis weight of the nonwoven fabric prepared from fibers having a polyvinyl alcohol component is 5 to 20 g / m ² and the thickness is 15 to 60 μm.

  The multilayer laminated paper of the present invention has an upper layer paper layer, a nonwoven fabric layer composed of fibers having at least a component of polyvinyl alcohol, and a lower layer paper layer.

  The multilayer laminated paper of the present invention is characterized in that the fiber having a polyvinyl alcohol component is a single fiber or a core-sheath type composite fiber.

  The multilayer laminated paper of the present invention is characterized in that the core-sheath type composite fiber is made of a resin having a core portion having a heat fusion temperature exceeding 120 ° C., and the sheath portion has a heat fusion temperature lower than that of the core portion. To do.

  The multilayer laminated paper of the present invention is characterized in that the heat-sealing temperature of the fiber having a polyvinyl alcohol component is within the range of 70 to 120 ° C. in the drying section of the paper machine.

  The multilayer laminated paper of the present invention is characterized in that the fiber having a polyvinyl alcohol component has a fiber length of 2 to 9 mm and a thickness of 0.6 to 5.6 dtex.

The multilayer laminated paper of the present invention is characterized in that the basis weight of a nonwoven fabric produced from fibers having a polyvinyl alcohol component is 5 to 20 g / m ² and the thickness is 15 to 60 μm.

  PVA fibers are hydrophilic raw materials, have good affinity between the nonwoven fabric and the upper and lower pulp paper stocks, and can prevent delamination due to hydrogen bonding with the pulp fibers.

  Further, PVA has a wet heat melting property and has a property of melting when moisture and heat are present. Due to this property, the upper and lower layers of the pulp paper material and the non-woven fabric exist because heat of 70 to 120 ° C. and moisture of the pulp fiber (wet paper) are present in the drying process after being combined with the pulp fiber on the long paper machine. The intermediate layer PVA fiber is thermally fused to prevent delamination.

  PVA fiber is a fiber that has the characteristics of both hydrophilicity, which is a characteristic of rayon fiber, and heat-fusibility, which is a characteristic of polyethylene fiber, polyester fiber, and polypropylene fiber. Suitable for preventing peeling.

  Moreover, since the nonwoven fabric used for this invention is manufactured with a wet nonwoven fabric manufacturing method, since the nonwoven fabric manufactured with the wet nonwoven fabric manufacturing method has uniform formation, the suitability of the functional printing to a nonwoven fabric is favorable. In addition, since the formation is uniform, a uniform formation of multilayer paper produced by joining on a long paper machine can be obtained.

  As a non-woven fabric, a core made of a PVA fiber made of a resin having a heat fusion temperature of the fiber core portion exceeding 120 ° C., and a heat fusion temperature of the sheath portion in the range of a heating drying temperature of 70 to 120 ° C. in a long paper machine. By using the sheath type composite fiber, it is possible to prevent shrinkage of the nonwoven fabric composed of the fiber and the fiber in the drying process of the long paper machine. When the nonwoven fabric passes through the drying process, the sheath portion of the core-sheath composite fiber is melted by heat, whereas the core portion is not melted due to the high heat-sealing temperature, and the core remains. This is because the core plays a role like a fiber reinforcement.

  DESCRIPTION OF EMBODIMENTS Embodiments of a PVA fiber used in the present invention, a non-woven fabric manufactured using PVA fibers, a multi-layer bonded paper manufactured using a non-woven fabric, and a multi-layer bonded paper manufacturing apparatus will be described with reference to the drawings.

  Fig.1 (a) shows the cross-section of the single fiber used for the nonwoven fabric in this invention, (b) shows the cross-section of a core-sheath-type composite fiber. FIG. 2 shows a cross-sectional view of the multilayer laminated paper in the present invention. FIG. 3 shows the overall configuration of the multilayer laminated paper manufacturing apparatus according to the present invention. FIG. 4 shows the characteristics and peel strength of the fibers of Examples and Comparative Examples in the present invention.

  First, the PVA fiber used in the present invention is a synthetic fiber containing polyvinyl alcohol as a component, and is manufactured into a fiber form by a wet spinning method. Further, the water solubility and the melting point are adjusted by changing the degree of saponification of PVA, and the heat fusion temperature is preferably 90 to 120 ° C. Moreover, as a structure of PVA fiber, a single fiber or a core-sheath type composite fiber is preferable.

  The heat sealing temperature here is a temperature at which wet-heat melting PVA fiber is temporarily heated to melt and fix.

  FIG. 1A shows a cross-sectional structure of a single fiber. A single fiber is a fiber composed of only one kind of component.

  FIG. 1B shows a cross-sectional structure of the core-sheath composite fiber. The core-sheath type composite fiber is a fiber in which the fiber component of the core part and the fiber component of the sheath part are different, or the fiber component of the core part and the fiber component of the sheath part are the same, but heat fusion Fibers with different temperatures.

  Although the core-sheath-type composite fiber of this invention will not be specifically limited if the component of the fiber of a sheath part (2) is comprised from the PVA component, The heat sealing | fusion temperature should be 90-120 degreeC. preferable. Further, the fiber component of the core part (3) may be a resin having a heat fusion temperature exceeding 120 ° C., for example, polyethylene terephthalate (PET), or a PVA component having a heat fusion temperature exceeding 120 ° C. preferable.

  This is because the heat-drying temperature in the drying process in the long paper machine is 70 to 120 ° C., whereas the heat-sealing temperature of the sheath portion of the core-sheath composite fiber is 90 to 120 ° C., and the core portion is heat-sealed. A fiber having a temperature exceeding 120 ° C. is used. That is, when the multilayer laminated paper passes through the drying process of the long paper machine, only the sheath portion of the core-sheath type composite fiber constituting the nonwoven fabric is melted, and the core portion does not melt because the heat-sealing temperature is high. This is to prevent shrinkage of the nonwoven fabric because the core serves as a fiber reinforcing material.

  Next, the multilayer laminated paper manufactured using a nonwoven fabric is demonstrated. FIG. 2 shows a cross-sectional view of the multilayer laminated paper. The multilayer laminated paper (4) has an upper paper layer (5) made of fibers, an intermediate layer made of non-woven fabric (6) having PVA fibers, and a lower paper layer (7) made of fibers.

As conditions for the nonwoven fabric (6), the basis weight is 5 to 20 g / m ² , the thickness is 15 to 60 μm, the fiber length constituting the nonwoven fabric is ² to 5 mm, and the fiber thickness is 0.6 to 5.6 dtex. Are preferred. Further, it is preferable that the water permeability is in the order of 4 seconds according to the drainage time measurement method, and the WET tensile strength is 1.0 kgf / 50 mm or more in the longitudinal direction and 0.3 kgf / 50 mm or more in the transverse direction.

  The fibers used in the upper paper layer (5) and the lower paper layer (7) are not particularly limited, and chemical pulps such as KP and SP made from plant fibers such as wood and cotton, GP and TMP , Pulp such as mechanical pulp such as CTMP, recycled paper recycled pulp and the like can be selected as appropriate.

  Here, the multi-layer laminated paper (4) has been described with a three-layer structure of the upper paper layer (5), the nonwoven fabric (6), and the lower paper layer (7), but the upper paper layer (5) sandwiching the nonwoven fabric (6). ) And the lower paper layer (7), a multi-layer structure such as four layers or five layers may be used.

  As a method for producing a nonwoven fabric, a wet nonwoven fabric production method is used. In the wet nonwoven fabric manufacturing method, first, the raw material fibers are uniformly dispersed in water, and the suspension in which the fibers are dispersed is poured onto a wire that circulates. To form. Next, the water remaining on the sheet is dehydrated in the press section, evaporated in the dryer section, and the dried sheet is wound up in the reel section for manufacturing. When the raw material is a synthetic fiber, an adhesive or binder fiber is added to the suspension in which the fibers are dispersed in order to bond the fibers. Then, the adhesive or binder fiber is melted by the heat of the dryer section to bond the fibers.

  Next, a long web paper machine, which is an apparatus for producing multilayer laminated paper, will be described. FIG. 3 shows the overall configuration of the long net paper machine. The long net paper machine (8) comprises a net band and has a circulating wire (9) for endless papermaking. The wire (9) is bridged between the driven pulley (10) and the driving pulley (11), and is supported by a plurality of rolls (not shown) arranged on the inner side along the wire (9). Has been circulating.

  From the upstream side to the downstream side of the upstream portion of the wire (9), the lower layer stock supply tank (12), the nonwoven fabric supply device (13), the upper layer stock supply tank ( 14) are sequentially arranged at intervals.

  The lower layer stock supply tank (12) and the upper layer stock supply tank (14) are respectively filled with the lower layer stock (15) and the upper layer stock (16), and are appropriately replenished from a supply source (not shown). The liquid level is controlled to be maintained. The lower layer stock (15) and the upper layer stock (16) are materials that are materials for the lower paper layer (7) and the upper paper layer (5), and are mainly composed of pulp fibers, water, and additives.

  In the downstream portion of each of the lower layer material supply tank (12) and the upper layer material supply tank (14), a lower sheet material sealing plate (17) and an upper layer material sealing plate (18) are respectively arranged. Has been. The lower layer paper and the upper layer paper are respectively placed on the wire (9) through the gaps between the lower sheet material sealing plate (17) and the upper layer material sealing plate (18) and the wire (9). Supply paper and make paper.

  The nonwoven fabric supply part by the nonwoven fabric supply device (13) is provided on the downstream side of the lower layer stock supply tank (12) and upstream of the upper layer stock supply tank (14), and is formed on the wire (9). The non-woven fabric (6) is supplied on the lower layer stock layer (wet paper) (19). The nonwoven fabric supply device (13) includes a nonwoven fabric supply drum (20) and a tension roll (21).

  The width of the strip-shaped nonwoven fabric (6) supplied from the nonwoven fabric supply device (13) is the lower layer paper formed by being supplied from the lower layer material sealing plate (17) to the upper surface (conveying surface) of the wire (9). Upper layer paper layer that is substantially the same as the width of the material layer (lower wet paper) (19), and is formed by being supplied from the upper layer material sealing plate (18) to the upper surface of the lower layer material layer (19). The width of (upper wet paper) (22) is substantially the same.

  The nonwoven fabric supply drum (20) can move along the longitudinal direction of the axis (direction perpendicular to the paper surface), that is, the width direction of the nonwoven fabric (6), and move the whole nonwoven fabric wound to adjust the position in the width direction. Moreover, it is the structure adjusted with the nonwoven fabric supply drum width direction position adjustment apparatus which is not shown in figure.

  A water squeezing box (23) is disposed below the wire (9) at the downstream side (the movement terminal portion on the upper surface of the wire). The water extraction box (23) sucks water contained in the lower layer paper layer (19), the nonwoven fabric (6) and the upper layer material layer (22) in the downstream portion of the wire (9) in the paper making process. And squeezing water.

  The multilayer laminated paper (4) formed of the wire (9) is guided by a guide roll (not shown) and wound up as a final product by a take-up roll, but the upstream side between the wire (9) and the take-up roll is upstream. From the side, a press roll (24) and a drying device (25) are arranged. A press roll (24) is used when giving a gap to a multilayer laminated paper. The drying device (25) is maintained at a temperature of 70 to 120 ° C.

  The press roll (24) sandwiches the multilayer laminated paper (4) and sends it to the downstream winding roll side. The gap is formed by a well-known press roll (24) or dandy roll (26). The drying device (25) uses a known drying device.

  The multilayer laminated paper (4) heated and dried by the drying device (25) is wound up by the reel device (27) to be completed as a product.

As the nonwoven fabric, PVA fibers having a single structure with a heat sealing temperature of 99 ° C. were used. The basis weight of the nonwoven fabric is 12 g / m ² , the thickness is 35 μm, the water permeability is 4 seconds according to the drainage time measurement method, and the WET tensile strength is 1.0 kgf / 50 mm in the longitudinal direction and 0.3 kgf / 50 mm in the transverse direction. .

A nonwoven fabric was inserted into the long net paper machine (8) shown in FIG. 3, and a multi-layered laminated paper was produced at a heating and drying temperature of 70 to 120 ° C. in the drying step. The peel strength of the produced multilayer laminated paper was 97 gf / 15 mm.
(Comparative Example 1)

As the nonwoven fabric, PET fiber having a heat fusion temperature of 110 ° C. was used. The basis weight of the nonwoven fabric is 20 g / m ² , the thickness is 70 μm, the water permeability is 4.10 seconds according to the filtration time measurement method, the WET tensile strength is 2.3 kgf / 50 mm in the longitudinal direction, and 1.3 kgf / 50 mm in the transverse direction. It is.

A nonwoven fabric was inserted into the long net paper machine (8) shown in FIG. 3, and a multi-layered laminated paper was produced at a heating and drying temperature of 70 to 120 ° C. in the drying step. The peel strength of the produced multilayer laminated paper was 82 gf / 15 mm.
(Comparative Example 2)

As the nonwoven fabric, rayon fibers having no heat-fusibility were used. The basis weight of the nonwoven fabric is 20 g / m ² , the thickness is 85 μm, the water permeability is 4.14 seconds according to the filtration time measurement method, and the WET tensile strength is 1.4 kgf / 50 mm in the longitudinal direction and 0.3 kgf / 50 mm in the transverse direction. It is.

  A nonwoven fabric was inserted into the long net paper machine (8) shown in FIG. 3, and a multi-layered laminated paper was produced at a heating and drying temperature of 70 to 120 ° C. in the drying step. The peel strength of the produced multilayer laminated paper was 75.5 gf / 15 mm.

  FIG. 4 shows the fiber characteristics and peel strength of the multilayer laminated paper made in Example 1 and Comparative Examples 1 and 2. Example 1 is defined as level 1, comparative example 1 as level 2, and comparative example 2 as level 3.

  From these results, it can be seen that the peel strength of the multi-layered laminated paper in which the nonwoven fabric composed of PVA fibers of level 1 is joined to the intermediate layer is the highest. This is considered to be due to the property that the PVA component is highly hydrophilic and has a high affinity with the pulp stock and the property of heat-fusibility.

  Moreover, the nonwoven fabric using the PET fiber which is Level 2 also has a heat-fusible property like the PVA fiber, but has a low affinity with the pulp stock and has a peel strength that is lower than that of the PVA fiber. It is thought that it fell.

  Furthermore, rayon fibers of level 3 are characterized by good affinity with pulp stock, but do not have the property of heat-sealing. From this, it can be said that the peel strength was lower than that of the PVA fiber.

(A) shows the cross-sectional structure of the single fiber used for the nonwoven fabric in this invention, (b) shows the cross-sectional structure of a core-sheath-type composite fiber. Sectional drawing of the multilayer laminated paper in this invention is shown. The whole structure of the manufacturing apparatus of the multilayer laminated paper in this invention is shown. The characteristic and peeling strength of the fiber of the Example in this invention and a comparative example are shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Single fiber 2 Sheath part 3 Core part 4 Multilayer laminated paper 5 Upper paper layer 6 Nonwoven fabric 7 Lower paper layer 8 Long paper machine 9 Wire 10 Driven pulley 11 Drive pulley 12 Lower paper supply tank 13 Nonwoven fabric supply device 14 Upper layer stock supply tank 15 Lower layer stock 16 Upper layer stock 17 Seal plate for lower layer stock 18 Seal plate for upper stock 19 Lower stock layer (lower wet paper)
20 Nonwoven fabric supply drum 21 Tension roll 22 Upper layer stock layer (upper wet paper)
23 squeezing box 24 press roll 25 drying device 26 dandy roll 27 reel device

Claims (13)

A non-woven fabric is prepared in advance using fibers having at least a polyvinyl alcohol component, and the non-woven fabric made of the polyvinyl alcohol is combined between an upper layer stock and a lower layer stock on a paper machine, and an upper layer stock layer and a non-woven fabric layer And a multilayer laminated paper having a lower paper layer, and the multilayer laminated paper is heated and dried in a drying section of the paper machine. The paper machine is a long paper machine, and at least supplies the upper layer paper by an upper layer paper supply tank on a wire, supplies the non-woven fabric by a non-woven fabric supply device, and supplies the lower layer paper by a lower layer paper supply tank. 2. The method of producing a multilayer laminated paper according to claim 1, wherein moisture is removed from the multilayer laminated paper that has been fed together by using a watering box and a press roll, and dried by a heat drying apparatus. . 3. The method for producing a multilayer laminated paper according to claim 1, wherein the fiber having a polyvinyl alcohol component is a single fiber or a core-sheath type composite fiber. The core-sheath type composite fiber is made of a resin having a core portion having a heat fusion temperature exceeding 120 ° C, and the sheath portion has a heat fusion temperature lower than that of the core portion. A method for producing multilayer laminated paper. The multilayer bonding according to any one of claims 1 to 4, wherein a heat-sealing temperature of the fiber having the polyvinyl alcohol component is in a range of a heating drying temperature of 70 to 120 ° C of the drying unit in the paper machine. Paper manufacturing method. 6. The method for producing a multilayer laminated paper according to claim 1, wherein the fiber having the polyvinyl alcohol component has a fiber length of 2 to 9 mm and a thickness of 0.6 to 5.6 dtex. 6. The multilayer laminated paper according to claim 1, wherein the basis weight of the nonwoven fabric produced from the fibers having the polyvinyl alcohol component is 5 to 20 g / m ² and the thickness is 15 to 60 μm. Method. A multilayer laminated paper having an upper layer paper layer, a non-woven fabric layer comprising fibers having at least a polyvinyl alcohol component, and a lower layer paper layer. The multilayer laminated paper according to claim 8, wherein the fiber having the polyvinyl alcohol component is a single fiber or a core-sheath type composite fiber. The core-sheath type composite fiber is made of a resin having a core portion having a heat fusion temperature exceeding 120 ° C, and the sheath portion has a heat fusion temperature lower than that of the core portion. Multi-layer laminated paper. The multi-layered laminate according to any one of claims 8 to 10, wherein a heat-sealing temperature of the fiber having the polyvinyl alcohol component is within a range of a heating drying temperature of 70 to 120 ° C of the drying unit in the paper machine. paper. The multilayer laminated paper according to any one of claims 8 to 11, wherein the fiber having a polyvinyl alcohol component has a fiber length of 2 to 9 mm and a thickness of 0.6 to 5.6 dtex. The multilayer laminated paper according to any one of claims 8 to 12, wherein a basis weight of the non-woven fabric made of the fibers having the polyvinyl alcohol component is 5 to 20 g / m ² and a thickness is 15 to 60 µm.

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